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We thank Prof. Atamanalp and colleagues for their interest and valuable comments on our article. The authors have highlighted important considerations in the diagnosis of sigmoid volvulus (SV). We would like to respond to their comments. Firstly, although we agree with their opinion that CT, MRI, and endoscopy are more reliable diagnostic tools than plain radiography, we still emphasize that diagnostic imaging for SV is initially based on plain radiography, as recommended by the WSES consensus guidelines. Since SV is the third most common cause of colonic obstruction worldwide, the accessibility of plain radiography is crucial. Among the many plain radiographic signs of SV, Levsky et al. reported that the most sensitive signs were absence of rectal gas, followed by inverted-U appearance and coffee bean sign. Understanding these signs may lead to early detection of SV and further CT evaluation for ischemia or perforation. Despite the high value of plain radiography, there is a global tend to use CT instead from the outset. Secondly, we agree with their opinion that endoscopy is not only a therapeutic, but also a diagnostic procedure to assess mucosal viability. In addition, we believe that endoscopy is also useful in ruling out other obstructive lesions, including colorectal neoplasia and complicated sigmoid diverticular disease. In the clinical setting, endoscopy is performed after the diagnosis of SV by plain radiography or CT and serves as the first line of decompression of SV when ischemia or perforation is not suspected. Finally, we congratulate Prof. Atamanalp and colleagues for their dedicated contribution to the large-scale SV studies in Eastern Anatolia, Turkey, where SV is endemic.
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BACKGROUND: The Guidelines for the Management of Cough and Sputum (2019) of the Japanese Respiratory Society (JRS) were the first internationally published guidelines for the management of sputum. However, the data used to determine the causative diseases of bloody sputum and hemoptysis in these guidelines were not obtained in Japan. METHODS: A retrospective analysis was performed using the clinical information of patients with bloody sputum or hemoptysis who visited the department of respiratory medicine at a university or core hospital in Japan. RESULTS: Included in the study were 556 patients (median age, 73 years; age range, 21-98 years; 302 males (54.3%)). The main causative diseases were bronchiectasis (102 patients (18.3%)), lung cancer (97 patients (17.4%)), and non-tuberculous mycobacterial disease (89 patients (16%)). Sex and age differences were observed in the frequency of causative diseases of bloody sputum and hemoptysis. The most common cause was lung cancer in males (26%), bronchiectasis in females (29%), lung cancer in patients aged <65 years (19%), and bronchiectasis in those aged >65 years (20%). CONCLUSIONS: The present study is the first to investigate the causative diseases of bloody sputum and hemoptysis using data obtained in Japan. When investigating the causative diseases of bloody sputum and hemoptysis, it is important to take the sex and age of the patients into account.
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Bronquiectasia , Neoplasias Pulmonares , Pneumologia , Masculino , Feminino , Humanos , Idoso , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso de 80 Anos ou mais , Hemoptise/epidemiologia , Hemoptise/etiologia , Escarro/microbiologia , Japão/epidemiologia , Hospitais Universitários , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Bronquiectasia/epidemiologia , Bronquiectasia/complicações , Neoplasias Pulmonares/complicações , Neoplasias Pulmonares/epidemiologiaRESUMO
BACKGROUND: 5-aminolevulinic acid (5-ALA), a natural amino acid that is marketed alongside sodium ferrous citrate (SFC) as a functional food, blocks severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) proliferation in vitro and exerts anti-inflammatory effects. In this phase II open-label, prospective, parallel-group, randomized trial, we aimed to evaluate the safety and efficacy of 5-ALA in patients with mild-to-moderate coronavirus disease 2019. METHODS: This trial was conducted in patients receiving 5-ALA/SFC (250/145 mg) orally thrice daily for 7 days, followed by 5-ALA/SFC (150/87 mg) orally thrice daily for 7 days. The primary endpoints were changes in SARS-CoV-2 viral load, clinical symptom scores, and 5-ALA/SFC safety (adverse events [AE] and changes in laboratory values and vital signs). RESULTS: A total of 50 patients were enrolled from 8 institutions in Japan. The change in SARS-CoV-2 viral load from baseline was not significantly different between the 5-ALA/SFC (n = 24) and control (n = 26) groups. The duration to improvement was shorter in the 5-ALA/SFC group than in the control group, although the difference was not significant. The 5-ALA/SFC group exhibited faster improvement rates in "taste abnormality," "cough," "lethargy," and "no appetite" than the control group. Eight AEs were observed in the 5-ALA/SFC group, with 22.7% of patients experiencing gastrointestinal symptoms (decreased appetite, constipation, and vomiting). AEs occurred with 750/435 mg/day in 25.0% of patients in the first phase and with 450/261 mg/day of 5-ALA/SFC in 6.3% of patients in the second phase. CONCLUSION: 5-ALA/SFC improved some symptoms but did not influence the SARS-CoV-2 viral load or clinical symptom scores over 14 days. The safety of 5-ALA/SFC in this study was acceptable. Further evaluation using a larger sample size or modified method is warranted.
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Ácido Aminolevulínico , COVID-19 , Humanos , Ferro , Fosfatos , Estudos Prospectivos , SARS-CoV-2RESUMO
Introduction: Two-dimensional cell cultures have contributed substantially to lung cancer research, but 3D cultures are gaining attention as a new, more efficient, and effective research model. A model reproducing the 3D characteristics and tumor microenvironment of the lungs in vivo, including the co-existence of healthy alveolar cells with lung cancer cells, is ideal. Here, we describe the creation of a successful ex vivo lung cancer model based on bioengineered lungs formed by decellularization and recellularization. Methods: Human cancer cells were directly implanted into a bioengineered rat lung, which was created with a decellularized rat lung scaffold reseeded with epithelial cells, endothelial cells and adipose-derived stem cells. Four human lung cancer cell lines (A549, PC-9, H1299, and PC-6) were applied to demonstrate forming cancer nodules on recellularized lungs and histopathological assessment were made among these models. MUC-1 expression analysis, RNA-seq analysis and drug response test were performed to demonstrate the superiority of this cancer model. Results: The morphology and MUC-1 expression of the model were like those of lung cancer in vivo. RNA sequencing revealed an elevated expression of genes related to epithelial-mesenchymal transition, hypoxia, and TNF-α signaling via NF-κB; but suppression of cell cycle-related genes including E2F. Drug response assays showed that gefitinib suppressed PC-9 cell proliferation equally well in the 3D lung cancer model as in 2D culture dishes, albeit over a smaller volume of cells, suggesting that fluctuations in gefitinib resistance genes such as JUN may affect drug sensitivity. Conclusions: A novel ex vivo lung cancer model was closely reproduced the 3D structure and microenvironment of the actual lungs, highlighting its possible use as a platform for lung cancer research and pathophysiological studies.
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Background: Thymic epithelial tumors (TETs) are prone to developing in East Asian populations. However, little is known about the genomic profile of TETs in East Asian populations, and the genomic aberrations in TETs have not yet been fully clarified. Thus, molecular targeted therapies for patients with TETs have not been established. This prospective study was conducted to explore the genetic abnormalities of surgically resected TETs in a Japanese cohort and to identify clues for carcinogenesis and potential therapeutic targets in TETs. Methods: Genetic profiles of TETs were investigated using fresh-frozen specimens resected from operable cases with TETs. DNA sequencing was performed using a next-generation sequencing (NGS) gene panel test with Ion Reporter™ and CLC Genomics Workbench 11.0. The mutation sites were further confirmed by Sanger sequencing, digital droplet polymerase chain reaction (ddPCR), and TA cloning for validation. Results: Among 43 patients diagnosed with anterior mediastinal tumors between January 2013 and March 2019, NGS and validation analyses were performed in 31 patients [29 thymomas and two thymic cancers (TCs)] who met the study criteria. Of these, 12 cases of thymoma types A, AB, B1, and B2 harbored the general transcription factor 2-I (GTF2I) mutation (L424H). Conversely, the mutation was not detected in type B3 thymoma or TC, suggesting that the GTF2I mutation existed in indolent types of TETs. Rat sarcoma viral oncogene (RAS) mutations were detected in three cases [Harvey RAS (HRAS) in two cases of type AB thymoma and neuroblastoma RAS (NRAS)] in one case of type B1 thymoma), and additional sex combs like 1 (ASXL1) mutation was present in one case of TC. All RAS mutations were observed in GTF2I-mutated cases. Conclusions: The GTF2I mutation (L424H) is the most frequently occurring mutation in the limited histology of thymoma, consistent with those in the non-Asian population. HRAS and NRAS mutations co-occurred in cases harboring the GTF2I mutation. These findings suggest that the existence of the GTF2I mutation might be related to indolent types of TETs, and RAS mutations could be candidates as therapeutic targets in TETs.
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A 36-year-old Japanese man presented with cavities and nodular shadows in the lower lobes of his lungs and osteolytic lesions in the thoracic spine. He was diagnosed with multisystem Langerhans cell histiocytosis (LCH). Three years earlier, he had been noted to have small cavities and granular lesions noted in the upper lobes of his lungs, which later improved with smoking cessation. It was likely that his single-system pulmonary LCH (PLCH) progressed to multisystem LCH despite smoking cessation. Relapse or progression may occur in cases where PLCH lesions improve after smoking cessation. Thus, close follow-up is vital.
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Histiocitose de Células de Langerhans , Abandono do Hábito de Fumar , Masculino , Humanos , Adulto , Histiocitose de Células de Langerhans/diagnóstico por imagem , Histiocitose de Células de Langerhans/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Tomografia Computadorizada por Raios X , RecidivaRESUMO
A 26-year-old Japanese woman was admitted with a 1-month history of diarrhea, a high fever for a few days, and exacerbation of dyspnea. She was treated with an antifibrotic drug and long-term oxygen therapy for Hermansky-Pudlak syndrome-related pulmonary fibrosis. New ground-glass attenuation appeared on chest computed tomography (CT), and a colon biopsy showed an inflammatory cell accumulation with a high titer of myeloperoxidase (MPO)-specific anti-neutrophil cytoplasmic antibodies (ANCA). Systemic inflammation related to MPO-ANCA titer elevation was suspected. Steroid pulse therapy and intravenous cyclophosphamide improved chest CT findings and diarrhea. Therefore, immunosuppressant treatment should be considered for systemic inflammation related to MPO-ANCA.
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Anticorpos Anticitoplasma de Neutrófilos , Síndrome de Hermanski-Pudlak , Feminino , Humanos , Adulto , Síndrome de Hermanski-Pudlak/complicações , Síndrome de Hermanski-Pudlak/diagnóstico , Peroxidase , Inflamação , DiarreiaRESUMO
BACKGROUND: Cryptococcal meningitis (CM) is an opportunistic infectious disease that occurs in immunocompromised hosts, not only in patients living with HIV, but also in patients without HIV. The evidence regarding the treatment for CM in patients without HIV is mainly found in small retrospective studies and is extremely limited. OBJECTIVES: In the present study, we compared the efficacy of liposomal amphotericin B (L-AMB) alone and in combination with flucytosine (5-FC) for the induction treatment of CM in patients without HIV. PATIENTS/METHODS: Data were gathered from the Japanese Diagnosis Procedure Combination database obtained from hospitals throughout Japan. The study included 517 patients without HIV but having CM who fulfilled the inclusion and exclusion criteria. We analysed the average effect of adding 5-FC to L-AMB treatment using the survival time within 14 days of the diagnosis after adjustment of the baseline clinical characteristics with associations with both selections of the treatment and the prognosis. RESULTS: A total of 146 and 217 CM patients received L-AMB and L-AMB with 5-FC, respectively, within 7 days of diagnosis. L-AMB with 5-FC showed better prognosis than L-AMB on day 14 (mortality 6% vs. 11%, hazard ratio, 0.5775; 95% confidence interval, 0.2748-1.213; p = 0.1, Wald test). CONCLUSIONS: From the results of this real-world database study, we revealed that the combination therapy of 5-FC on L-AMB for induction therapy might have an advantage on the survival time of NHNT patients with CM as well as PLHIV patients with CM.
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Meningite Criptocócica , Anfotericina B , Antifúngicos , Quimioterapia Combinada , Flucitosina/uso terapêutico , Humanos , Meningite Criptocócica/tratamento farmacológico , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Allergic bronchopulmonary aspergillosis (ABPA) and chronic pulmonary aspergillosis (CPA) are important fungal infections caused by Aspergillus species. An overlap of ABPA and CPA has been reported; therefore, it is critical to determine whether the main pathology is ABPA or CPA and whether antifungals are required. In this study, we investigated whether the serum cytokine profile is useful for understanding the pathology and for differentiating between these diseases. We compared the various serum cytokine levels among healthy subjects and patients diagnosed with asthma, ABPA, or CPA at Nagasaki University Hospital between January 2003 and December 2018. In total, 14 healthy subjects, 19 patients with asthma, 11 with ABPA, and 10 with CPA were enrolled. Interleukin (IL) -5 levels were significantly higher in patients with ABPA than in those with CPA, and IL-33 and tumor necrosis factor (TNF) levels were significantly higher in patients with CPA than in those with asthma (p < 0.05, Dunn's multiple comparison test). The sensitivity and specificity of the IL-10/IL-5 ratio (cutoff index 2.47) for diagnosing CPA were 70% and 100%, respectively. The serum cytokine profile is useful in understanding the pathology of ABPA and CPA, and the IL-10/IL-5 ratio may be a novel supplemental biomarker for indicating the pathology of CPA.
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Background: The lung cancer biopsy specimens obtained by endobronchial ultrasound-guide sheath (EBUS-GS) trans lung biopsy occasionally do not contain cancer cells. It is a problem that there is a possibility that they may not contain cancer cells. Aim of the study: To investigate the proportion of biopsy specimens containing cancer cells in total biopsy specimens. Materials & methods: Patients with lung cancer diagnosed by EBUS-GS were selected. The primary end point was the proportion of specimens containing tumors in the total specimens obtained by EBUS-GS. Results: Twenty-six patients were investigated. The percentage of specimens containing cancer cells in the total specimens was 79.0%. Conclusion: The proportion of biopsy specimens containing cancer cell to all biopsy specimens by EBUS-GS was high, but not 100%.
The lung cancer biopsy specimens obtained by trans lung biopsy occasionally do not contain cancer cells. It is a problem that there is a possibility that they may not contain cancer cells. If the biopsy specimens contained no malignant cells, there was a possibility that accurate genetic test would not be performed and as a result, the correct molecular targeted drug would not be used. It is important to investigate the proportion of biopsy specimens containing cancer cells in total biopsy specimens. In this study, we showed the percentage of specimens containing cancer cells in the total specimens was 79.0%. This result should be considered to perform genetic test from biopsy specimens.
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mTOR signaling may be a new therapeutic target for IL-6 inhibitor refractory iMCD-NOS.
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Hiperplasia do Linfonodo Gigante/tratamento farmacológico , Imunossupressores/uso terapêutico , Sirolimo/uso terapêutico , Adulto , Anticorpos Monoclonais Humanizados/uso terapêutico , Humanos , MasculinoRESUMO
A 60-year-old Japanese man with a history of heavy smoking came to our hospital for a detailed examination, suspecting interstitial pneumonia because of gradually increasing dyspnea on exertion over a period of one year. Chest high-resolution computed tomography revealed ground-glass shadows with emphysematous changes. Pathological analysis of samples obtained using transbronchial lung cryobiopsy revealed an accumulation of alveolar macrophages with abundant eosinophilic cytoplasm in the alveolar space. Following a multidisciplinary discussion, the patient was diagnosed with desquamative interstitial pneumonia. To our knowledge, this is the first detailed report of desquamative interstitial pneumonia diagnosed using transbronchial lung cryobiopsy.
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BACKGROUND: The recent increase in cases of azole-resistant Aspergillus fumigatus (ARAf) infections is a major clinical concern owing to its treatment limitations. Patient-derived ARAf occurs after prolonged azole treatment in patients with aspergillosis and involves various cyp51A point mutations or non-cyp51A mutations. The prognosis of patients with chronic pulmonary aspergillosis (CPA) with patient-derived ARAf infection remains unclear. In this study, we reported the case of a patient with ARAf due to HapE mutation, as well as the virulence of the isolate. CASE PRESENTATION: A 37-year-old male was presented with productive cough and low-grade fever. The patient was diagnosed with CPA based on the chronic course, presence of a fungus ball in the upper left lobe on chest computed tomography (CT), positivity for Aspergillus-precipitating antibody and denial of other diseases. The patient underwent left upper lobe and left S6 segment resection surgery because of repeated haemoptysis during voriconazole (VRC) treatment. The patient was postoperatively treated with VRC for 6 months. Since then, the patient was followed up without antifungal treatment but relapsed 4 years later, and VRC treatment was reinitiated. Although an azole-resistant isolate was isolated after VRC treatment, the patient did not show any disease progression in either respiratory symptoms or radiological findings. The ARAf isolated from this patient showed slow growth, decreased biomass and biofilm formation in vitro, and decreased virulence in the Galleria mellonella infection model compared with its parental strain. These phenotypes could be caused by the HapE splice site mutation. CONCLUSIONS: This is the first to report a case demonstrating the clinical manifestation of a CPA patient infected with ARAf with a HapE splice site mutation, which was consistent with the in vitro and in vivo attenuated virulence of the ARAf isolate. These results imply that not all the ARAf infections in immunocompetent patients require antifungal treatment. Further studies on the virulence of non-cyp51A mutations in ARAf are warranted.
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Aspergillus fumigatus/genética , Azóis/farmacologia , Farmacorresistência Fúngica/efeitos dos fármacos , Proteínas Fúngicas/genética , Aspergilose Pulmonar/microbiologia , Adulto , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Aspergillus fumigatus/efeitos dos fármacos , Aspergillus fumigatus/isolamento & purificação , Aspergillus fumigatus/patogenicidade , Azóis/uso terapêutico , Doença Crônica , Humanos , Masculino , Testes de Sensibilidade Microbiana , Mutação , Fenótipo , Aspergilose Pulmonar/tratamento farmacológico , Virulência/genética , Voriconazol/uso terapêuticoRESUMO
A 60-year-old Japanese woman presented with subacute progressive muscle pain and weakness in her proximal extremities. She was diagnosed with influenza A (H3N2) infection a week before the onset of muscle pain. At the time of admission, she exhibited weakness in the proximal muscles of the upper and lower limbs, elevated serum liver enzymes and creatinine kinase, and myoglobinuria. She did not manifest renal failure and cardiac abnormalities, indicating myocarditis. Electromyography revealed myogenic changes, and magnetic resonance imaging of the upper limb showed abnormal signal intensities in the muscles, suggestive of myopathy. Muscle biopsy of the biceps revealed numerous necrotic regeneration fibers and mild inflammatory cell infiltration, suggesting immune-mediated necrotizing myopathy (IMNM). Necrotized muscle cells were positive for human influenza A (H3N2). Autoantibody analysis showed the presence of antibodies against the signal recognition particle (SRP), and the patient was diagnosed with anti-SRP-associated IMNM. She was resistant to intravenous methylprednisolone pulse therapy but recovered after administration of oral systemic corticosteroids and immunoglobulins. We speculate that the influenza A (H3N2) infection might have triggered her IMNM. Thus, IMNM should be considered as a differential diagnosis in patients with proximal muscle weakness that persists after viral infections.
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Doenças Autoimunes/diagnóstico , Doenças Autoimunes/microbiologia , Vírus da Influenza A Subtipo H3N2/isolamento & purificação , Influenza Humana/complicações , Doenças Musculares/diagnóstico , Doenças Musculares/microbiologia , Partícula de Reconhecimento de Sinal/imunologia , Autoanticorpos/análise , Doenças Autoimunes/imunologia , Doenças Autoimunes/patologia , Biópsia , Diagnóstico Diferencial , Feminino , Humanos , Influenza Humana/diagnóstico , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Doenças Musculares/imunologia , Doenças Musculares/patologia , Mialgia/diagnóstico , NecroseRESUMO
Pneumocystis jirovecii pneumonia (PCP) is an opportunistic and life-threatening pulmonary infection with an increasing prevalence among individuals who are human immunodeficiency virus (HIV)-negative. Evidence regarding diagnostic testing of PCP in this patient population is insufficient. We evaluated the performance of serum (1, 3)-ß-d-glucan (BDG) using the Fungitec G-test MK kit for diagnosing PCP in non-HIV patients. We retrospectively analyzed data from 219 non-HIV adult patients who underwent bronchoscopy and were tested for P. jirovecii DNA by PCR using lavage samples from the lower respiratory tract. Fifty PCP patients and 125 non-PCP patients were included. The most common underlying diseases were malignancies and systemic autoimmune diseases. Using the serum BDG Fungitec G-test MK test to diagnose PCP, the area under the receiver operating characteristic curve (AUC) was 0.924, whereas the modified cut-off value of 36.6 pg/mL had a sensitivity and specificity of 92.0% and 84.8%, respectively. The AUC for patients with systemic autoimmune diseases was 0.873, and the accuracy of serum BDG test declined when using methotrexate (MTX). In conclusion, the serum BDG test was useful for diagnosing PCP in non-HIV patients; however, the results should be carefully interpreted in case of MTX administration. LAY SUMMARY: The Fungitec G-test MK kit for measuring serum (1, 3)-ß-d-glucan (BDG) levels had a sufficient diagnostic performance for Pneumocystis jirovecii pneumonia (PCP) in human immunodeficiency virus-negative patients. However, the results should be carefully interpreted in case of MTX administration.
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BACKGROUND: Vacuolar encephalomyelopathy, a disregarded diagnosis lately, was a major neurological disease in the terminal stages of human immunodeficiency virus (HIV)-1 infection in the pre-antiretroviral therapy (ART) era. Granulomatous-lymphocytic interstitial lung disease (GLILD) was classically identified as a non-infectious complication of common variable immunodeficiency; however, it is now being recognized in other immunodeficiency disorders. Here, we report the first case of GLILD accompanied by vacuolar encephalomyelopathy in a newly diagnosed HIV-infected man. CASE PRESENTATION: A 40-year-old Japanese man presented with chronic dry cough and progressing paraplegia. Radiological examination revealed diffuse pulmonary abnormalities in bilateral lungs, focal demyelinating lesions of the spinal cord, and white matter lesions in the brain. He was diagnosed with GLILD based on marked lymphocytosis detecting in bronchoalveolar lavage, and transbronchial-biopsy proven T-cellular interstitial lung disease with granulomas. Microbiological examinations did not reveal an etiologic agent. The patient was also diagnosed with HIV-associated vacuolar encephalomyelopathy on the basis of an elevated HIV viral load in cerebrospinal fluid. After initiating ART, the brain lesions and paraplegia improved significantly, and interstitial abnormalities of the lungs and cough disappeared. CONCLUSION: This report highlights that even in the post-ART era in developed countries with advanced healthcare services, HIV-associated vacuolar encephalomyelopathy should be considered in the differential diagnosis of a progressive neurological disorder during the first visit. Furthermore, GLILD may represent an HIV-associated pulmonary manifestation that can be treated by ART.
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Antirretrovirais/uso terapêutico , Infecções por HIV/complicações , Infecções por HIV/tratamento farmacológico , HIV/efeitos dos fármacos , Doenças Pulmonares Intersticiais/diagnóstico , Doenças por Armazenamento dos Lisossomos/virologia , Doenças Musculares/virologia , Adulto , Diagnóstico Diferencial , HIV/patogenicidade , Infecções por HIV/diagnóstico , Humanos , Pulmão/patologia , Doenças Pulmonares Intersticiais/virologia , Masculino , Vacúolos/patologiaRESUMO
Endobronchial volatile sulfur compounds in patients with lung abscess or lung cancer were measured using the Oral Chroma™ gas chromatograph. High levels of hydrogen sulfide and methyl mercaptan were observed in some patients with lung abscess but not in patients with lung cancer. Measuring endobronchial volatile sulfur compounds could be useful for the rapid diagnosis of lung abscess caused by obligate anaerobes.
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Bactérias Anaeróbias , Infecções Bacterianas/diagnóstico por imagem , Infecções Bacterianas/microbiologia , Brônquios/metabolismo , Cromatografia Gasosa/métodos , Abscesso Pulmonar/diagnóstico , Abscesso Pulmonar/microbiologia , Compostos de Enxofre/análise , Biomarcadores/análise , Humanos , Sulfeto de Hidrogênio/análise , Projetos Piloto , VolatilizaçãoRESUMO
Whether respiratory epithelial cells regulate the final transit of extravasated neutrophils into the inflamed airspace or are a passive barrier is poorly understood. Alveolar epithelial type 1 (AT1) cells, best known for solute transport and gas exchange, have few established immune roles. Epithelial membrane protein 2 (EMP2), a tetraspan protein that promotes recruitment of integrins to lipid rafts, is highly expressed in AT1 cells but has no known function in lung biology. Here, we show that Emp2-/- mice exhibit reduced neutrophil influx into the airspace after a wide range of inhaled exposures. During bacterial pneumonia, Emp2-/- mice had attenuated neutrophilic lung injury and improved survival. Bone marrow chimeras, intravital neutrophil labeling, and in vitro assays suggested that defective transepithelial migration of neutrophils into the alveolar lumen occurs in Emp2-/- lungs. Emp2-/- AT1 cells had dysregulated surface display of multiple adhesion molecules, associated with reduced raft abundance. Epithelial raft abundance was dependent upon putative cholesterol-binding motifs in EMP2, whereas EMP2 supported adhesion molecule display and neutrophil transmigration through suppression of caveolins. Taken together, we propose that EMP2-dependent membrane organization ensures proper display on AT1 cells of a suite of proteins required to instruct paracellular neutrophil traffic into the alveolus.